Medical Bulletin 6/February/2023

Here are the top medical news for the day:

New therapeutic target in macrophages identified for the treatment of obesity-related diseases

A team of researchers at the CNIC has discovered that the metabolic requirements of macrophages differ depending on the organ in which they reside. In other words, these cells adapt to the needs of the organ in which they are located.

The new study reveals that macrophages adapt their metabolism and function to the organ in which they reside. “In tissues with abundant extracellular fat and cholesterol, such as the lungs and spleen, macrophages adapt their metabolism to degrade these fats through mitochondrial respiration,” explained first author Dr. Stefanie Wculek. “Using genetic or pharmacological methods to disrupt mitochondrial respiration, mitochondria can be eliminated from lung and spleen, whereas the macrophages in other organs, which don’t depend on mitochondrial respiration, survive.”

Reference:

Oxidative phosphorylation selectively orchestrates tissue macrophage homeostasis,Immunity,doi 10.1016/j.immuni.2023.01.011

Study reveals circadian gene expression varies according to sex and age

Daily rhythms of gene expression in humans vary according to sex and age, according to a new study using more than 900 human transcriptomes from the Genotype-tissue Expression (GTEx) project. The findings reveal a previously unknown diversity of sex- and age-specific differences in circadian gene expression, which could help explain the different incidences of some diseases in males and females, as well as during aging.

To better understand the interactions between sexual dimorphism and the molecular circadian rhythms in humans, researchers combined RNA sequencing data from 914 human donors with an algorithm that used temporal markers within tissues to detect and time-stamp each individual’s transcriptome with a circadian phase. The approach allowed the authors to view 24-hour gene expression rhythms across 46 human tissues.

Reference:

Sex-dimorphic and age-dependent organization of 24 hour gene expression rhythms in human,Science,doi 10.1126/science.add0846

Kisspeptin hormone injection could treat low sex drive in women and men: Study

The hormone kisspeptin could be used to treat women and men distressed by their low sexual desire, according to two new studies. The studies found that giving kisspeptin can boost sexual responses in women and men who have hypoactive sexual desire disorder (HSDD) - a condition characterized by low sexual desire that is distressing to the individual. Kisspeptin is a naturally-occurring hormone that stimulates the release of other reproductive hormones inside the body.

These two clinical trials involved 32 pre-menopausal women and 32 men with HSDD. In both studies, patients underwent scanning of the brain using MRI, as well as blood and behavioural tests. Kisspeptin administration improved sexual brain processing in both women and men, resulting in positive effects on sexual behaviour compared to placebo.

Reference:

Dr Alexander Comninos et al, JAMA Network Open,IMPERIAL COLLEGE LONDON